SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ecfc860acfd179a1de45c28915e77474626897988444276035c45d448238be60' 
  AND token = 'aeul7epwhCsMOpk/kc/uGkBASclA0JLxP4eDGmbEMfg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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