SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e622f30774c18530c51683e48c1dca1b94c891f6740c80aaaed4eff6769b5e70' 
  AND token = 'aajkuVZsHCxl8WnKtZ6WIGHmYv+NBNarT2SKXP/9RjY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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