SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f64d5f8dbdd86dafce5f7832586f5b0f0093ca987e293774951dd9285ffc290' 
  AND token = 'AfuuFU9PuCGVLIsDtPum/CJgp6QhyY+JvZ87oXBbBlM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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