SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b29ede1b3e1a6d0183a6818a34550374d168ecdc6a437bdf15d53860de9aff4f' 
  AND token = 'MHcBBQGmtm4+sPkkO9kr/DGCrLo/eGHGACHinisgmxk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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