SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7fd5b2aae5292f5879a7b2bf99ab3dee0ea512f2887886bac17cd8b211225276' 
  AND token = 'LfmpORGqllsuhsk+Yo+9AMPFiiweHNepzY1cIVcbk9g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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