SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60b07b20af5e0cff1c9a3d708fab68114c4c1f5c1f466d5800ed53ee6b39e387' 
  AND token = 'P6TudbMXyt5Eh9AoAExFC55K/gXFK43Ss/RONBTuUgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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