SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14a03a4a3495d16dafd5b7c81c1feb75b0e01cf5f6206a95031ff2b1112fa9fd' 
  AND token = 'Z3edsGY3HdtQlebMkMPsNnoOhsVtXCmDNxkhCf0Erro=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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