SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf4900677b2b3939233c13357d187e42f621bdb4774e46006ff301d98a633879' 
  AND token = 'lFEbkfFluZJaBSy+eb0lL5pSePQZoV4YhizljXximuo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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