SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd612211443dfbe98829474da7d85483c4f4f493037e695639b67b3ed2636a1e5' 
  AND token = 'yBrm2VkFuiCijrhiLBgY4FoxgNxtPOOpQhGkAW0IiZo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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