SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28e860b50c1667977dc78738be125e16584f45343087ae071706332eecf86e63' 
  AND token = 'eOJyDdE4kimjhE909zDvfCQce+cdRbr0qYGdq2Gbpkg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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