SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ead70f91e7a766355c31fe0dd181fb45a3905fc9a0671214beaf336dc566613a' 
  AND token = '8WmFY5N2an8EVTMUsGcIOcsWik8K0OaxkVgS28u0l+8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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