SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ebc72d6ce78628fe50cd98eecc86557eb7c494a2514c880031426a436029aa0e' 
  AND token = 'fwFEUD4QsI6XDInmQUIlyTtp8cBx2USOXc3TqMyDSS0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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