SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8557ec0effbfc93af7e46bd2e34084fd359086ac99b094455776bec5099f7db5' 
  AND token = 'YGXspZC1DrnCvU/rHqi0Ag0ocwthsXPnU/rPqdu99bs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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