SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '772fd40d75fe5dfe223eca1a99c92feba278506dbc4d6bf97ed7257e498931ab' 
  AND token = '7FuUFJXufSF8KiCZm/zRC9pTMx3INI4imjURPIysuFs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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