SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7120fe8d13f9f150af92aa8476bdcfdafc1b66056dc574602fcfa136beeeac25' 
  AND token = '053W7hpHnF2dhB9AzLQTVevU7KUj7Nz6cojj+/b1lRQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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