SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '363869dca21b5cb2ce5ac09c86542724691fef925cd0f6431a0dfea39838f254' 
  AND token = 'Wi4ppFkJdaEXClZ+upouYX43eCZzrLxqT1jpa9H67D0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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