SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c25aee3c9a84283190602195721329b48cc48b7a6df9c1077f0341fe1934bd4' 
  AND token = 'h1oIa9DGOCbI5AJCaYZpB8MypLpr7gKtoO+CI/VrviE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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