SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c8338cf13bb0a724898843149719d6cb009cb641140fbd1de8806e0b3e66dd8' 
  AND token = 'bCYbspZbzkT5YVFHSgJRHqHK/RsaTC0gcYFOq/FInAY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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