SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c1cd1a03ecc831c293ab759686542fdb1e943588e19830014ea13b8cce07c8c' 
  AND token = 'XkFtpCwowi1X+pbRYWzw6v+hv63UTNz9WhPMtuPXYKQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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