SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd65d70eb026c629260f17830c30d3c4523fb46b804a1412ae81bfaac45b4d4da' 
  AND token = 'xDACLTERIext7QRyN9ViqxYHi+mGys+dCdmKAOtNnjQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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