SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85e885a373c987af025039cfced2c38e62447b32c46131eed4df7e338f85a0cb' 
  AND token = 'vO8yuSoYsp5VY8C6J6mi0RsqnKQqpVr8gFhG4/9TBUQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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