SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '90fdd6a8e0d0f5b795e442b8c7852a78c7ca6182e3366e58c963ef4c0a061437' 
  AND token = 'BBALxnIg1uUgp1yG7m5hLN/TJjq+Mv04CprLLqB6DY8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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