SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f64116f905e48dbeb5415ec391ad455ef3daed2f645b5316aa35cefa92a688d' 
  AND token = 'opUveCzeEIWtMORBdytT4omLrOG8WKjJvhmvuTzv9CM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}