SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '5df45f1aed2da33d2db04a09676e626b0eca18670fa503564de1afc89fdf3e92' 
  AND token = '7M6JkVQfRPJ8PvEgg4Mb+Y8RYQLQJtfP9MPRGVqwWSM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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