SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '46bf43ceeda088dd74765440e90b5c3fbea1904cfb9d69fed32cb7023a3642aa' 
  AND token = 'nYEx17y1tbLUMypiwNbFRDRTDNqsQBAHgzf90H4r1X0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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