SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e92108cf517225b92ce9b4ed13f969c74e1ca040ad41175c21f5bf3a5eec92f3' 
  AND token = 'mwSTK8ePk0ePRSE6x0hYFF9dq/s4JjYS4AYWgWGwv/E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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