SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7f6ae2764118413adf8fe5c885a1c2a7eef56b7e9c768042c62b6393fba77cb9' 
  AND token = 'YanhvCk1FCVG8nE6aM+NhpRH3aHQznwc02mBVqBuGPc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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