SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '55caf49cb39c5bd880f91428c09e69f778bf3f8c3954660fb0403d5d27bef2a0' 
  AND token = 'PwsKR5i9YAuWGBOwGbJUDYqmQ9zfdK7BtFFj6EdW9Co=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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