SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '487e7672c39d67dba18467d3e9e60a74c6a7233655be53f075bffe3e06417322' 
  AND token = 'NA9dq/ZHiihA4sun/hlitOLtlv7IlxgJ+zopTBTbbjs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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