SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4a51127f7d8b76d993154634f50a463af78eede9ac5fa2d5907c7cfe12d939d2' 
  AND token = 'mN7Hjmupm8+kmtAB8rF9qJuapkeXone7dRLSOACKHso=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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