SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0fec9b14daefcff5e622ab7be841e1dfb7008b5ae586db6622ced458bb566b0c' 
  AND token = 'Bcmgw0uJWFtOjeHMvnQCNkoNBrkLAwWRSoNcd7+9EcM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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