SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7cd04f68b1acf390b3c1d2dd430d8fdf4d30f3a742926927ab5e4cfb02252f2b' 
  AND token = 'UjBRekH7Phi5+Uywfw/RK2+PIHFzSGn6v5PUuvNIDx4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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