SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae1cc7e9944013d95140717fc73545c8135277c09d62ba11b0382cf24da68fca' 
  AND token = 'dpeSFkdxN4GB4yJerxH3wZ6tdDFFX3X1scY7YzOklKo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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