SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '638efbff5661b2ba16b95b122ca35adb5e525c6c28de1a0f3c89b4021b228b49' 
  AND token = 'jiGMWP6cRMtFHp18f8Hfw/1/HnwdZo+vkkKW/rX1yR0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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