SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a00da414e266055d7c3e3ced2c34e6adb48e28b44f5fb36f47b3be71a2ab4c89' 
  AND token = 'K+1z8Gyw2N+q64wwxb/qgaHFjjfRCVoZwIVBcSBBRoQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}