SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c477a767cf33550aa74cfafd6005d103f1ed1dffde2061d26db0962317dae34b' 
  AND token = '6kRgxOAOtF0kEMaeIrQJfIZHgT6xVwwX31YDncqk/hc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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