SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '14ab92dd482af116c8b767773f1ecf1fc1fcef18e96dba8cc2451c84a27f3d75' 
  AND token = 'IbIURga2QfoPgkVpbTN4svlIFqnY/kqv+84HZDKfqwY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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