SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b2de05438afc7b645b53e4d2578fa2e9898578f3178c8f327273c9ecdaf75ea8' 
  AND token = '0snzh7uCSP9M+zV9AUPHieeuReEiqgqYKGJQnAB18bk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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