SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f0e5da961002a3ae2a1f039e74be20cce6a810030dc320cfbf3a32b9505fb2a0' 
  AND token = 'hmzM2TcEngIaXqQYsYBJrMotvUjWFNEO9Uiy84NZgVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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