SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '764dbb26824403e2ead2258840246e894d997d8828398ea811539846a60ef5c7' 
  AND token = 'NtU8NGi2+lMXsgcRdcVerAMlNogCiu78j/eBTOlYyi0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}