SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2a3790b83fac434f8030d1735cf6c69fbb08165f3a64a79929b7ecad8782b0c' 
  AND token = 'v2UZphJVrJ5P5+EUOHEzg/AaKDX4cqxQ3owhu/ZKOJg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}