SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f56d2f19af86f47d7ee181be5948dca02b57de1942907f99dde8df2843beb6e0' 
  AND token = 'EcWJDuW4M0JrhEVQkop95wPqZFQlyaUNg1rAZo9MkMo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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