SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6bb847e4f8d7622a463c6cc5417d7e6924e8fe6147c5379d39d8d765190a93c9' 
  AND token = 'Nv8EAAP/gSsD4K7mD1s9UgY4pZ/BwG6sJBR8a44FvAw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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