SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '3a94156a51603ca5500ac1abcbbfb23cfb0fa0e01478e4b013055ee52c0093e2' 
  AND token = '2Aj4oe4Lw+a6OJrEC29fJQ0epS2qp8NPM+Fs2DNT75k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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