SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '35e8788c3f5865bd44a17e51bb0d59bb49e55792d23c97a0b52627c3230045b8' 
  AND token = 'bAkTuIR9fOcfygEvxHKYQ8XKOhe/nFbZFHWUDfrV8Xs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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