SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b295091a3e9faaa53e50853cd771257b6f64fae3e11241f3148d62eb9d44f890' 
  AND token = 'NyeYULMkKw9m73GegIed7CHqscGdjjCRYvOoSd8dGCI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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