SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0103f975c41dd8ef9961e318335db58ae38223ada85a152672d87f8b6dee72a0' 
  AND token = 'LNMKLrX1gd/OoJ+6ztE8WSutXjSVKqQed6uhtX2z/Kw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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