SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9cedb2bede2f64854aab9bd4c923ac85dbb90a34c0ab71c47eeda9875e4b325' 
  AND token = 'azV4X8+KR0l24AchNca7QRWr9CsvCaAnAiUOoYRIav8=' 
  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"
    }
  }
}