SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ebae34dbe8345acebb0a7527c06fed61e2f17f266b8507cb2ffe7cbdf32ccc19' 
  AND token = 'FMOaVMvPnqpqPpoEj/Gkz7dwjC9/JFPF4yhtYKQG1SI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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